This invention relates in general to a pump, and more particularly to a steam driven pump for draining fluid from a container.
Steam driven pumps and ejectors are useful in draining unwanted fluid from containers such as steam pits, tunnels, enclosed spaces, and the like. A typical conventional steam driven pump or ejector includes a tapered venturi channel or siphon and a float-operated piloted steam valve. As fluid in a container accumulates, a ball float raises upward until the upward motion of the float opens the pilot valve, which in turn fluidly actuates a second valve, and admits motive steam into the pump or ejector. The jet action of the motive steam creates a vacuum in the ejector, and entrains the fluid from the container, discharging both fluids under pressure through a discharge port. The ejector may include an on/off valve in which the valve is open within a first range of predetermined float levels and closed within a second range of predetermined float levels. Such pumps or ejectors are typically made of a combination of steel, stainless steel, copper, brass, and the like. The piloted steam valve is typically made of steel. Actuating mechanisms and piloted valves made of steel require frequent inspection to check for rust and other contaminants carried by the motive steam, which can cause fouling of the float lever assembly and the piloted valve.
Another typical conventional steam driven pump or ejector includes a tapered venturi channel or siphon, and a modulating float-operated valve, rather than an on/off piloted steam valve. Movement of the float along a shaft actuates the steam valve, and admits motive steam into the pump or ejector. The jet action of the motive steam creates a vacuum in the ejector, and entrains the fluid from the container, discharging both fluids under pressure through a discharge port. Such pumps or ejectors are also made from a combination of steel, stainless steel, copper, brass, and the like. In such a modulating valve design, it is possible for the motive steam to bleed past the valve and the valve seat, causing premature wear of the seat and failure of the pump.
It would therefore be advantageous to provide a pump that is reliable, resistant to corrosion, and has a long service life. It would also be advantageous to provide a pump that is compact in size, has a simple design, and is easy to maintain. It would further be advantageous to provide a pump that prevents bleeding of steam past the valve.
The above objects as well as other objects not specifically enumerated are achieved by a pump comprising: a housing having at least one fluid channel; a motive fluid inlet port; a suction fluid inlet port; and a discharge port. The pump also includes a venturi disposed in the fluid channel of the housing. The venturi is connected by way of the fluid channel to the motive fluid inlet port, the suction fluid inlet port, and the discharge port. A ball check valve is operatively disposed between the motive fluid inlet port and the venturi for controlling the flow of motive fluid. The pump further includes an actuator assembly for actuating the ball check valve. In the preferred embodiment, the ball check valve has only an opened position and a closed position.
In another embodiment of the invention, the pump includes a housing having at least one fluid channel; a motive fluid inlet port; a suction fluid inlet port; and a discharge port. The pump also includes a venturi disposed in the fluid channel of the housing. The venturi is connected by way of the fluid channel to the motive fluid inlet port, the suction fluid inlet port, and the discharge port. A valve having only an opened position and a closed position is operatively disposed between the motive fluid inlet port and the venturi for controlling the flow of motive fluid. The pump further includes an actuator assembly directly connected to the valve by a mechanical linkage for actuating the valve, and a suction fluid detector for detecting a level of suction fluid.
In an additional embodiment of the invention, the pump includes a housing having at least one fluid channel; a motive fluid inlet port; a suction fluid inlet port; and a discharge port. The pump also includes a venturi disposed in the fluid channel of the housing. The venturi is connected by way of the fluid channel to the motive fluid inlet port, the suction fluid inlet port, and the discharge port. A valve having only an opened position and a closed position is operatively disposed between the motive fluid inlet port and the venturi for controlling the flow of motive fluid. The pump further includes an actuator assembly directly connected to the valve by a mechanical linkage for actuating the valve, a suction fluid detector for detecting a level of suction fluid, and a container for containing suction fluid.
Various objects and advantages of this invention will become apparent to those skilled in the art from the following detailed description of the preferred embodiment, when read in light of the accompanying drawings.